# Add and Verify a Sending Domain

Domain verification proves that you control the domain and lets Prontuno authenticate the email sent on its behalf.

## Add the domain

1. Open **Domains** in the Prontuno dashboard.
2. Select **New Domain**.
3. Enter the domain used by your email’s `From` address.
4. Confirm you have access to its DNS settings, then select **Add Domain**.

Use a domain you control. Do not add a mailbox provider’s shared domain such as `gmail.com` or `yahoo.com`.

## Publish the DNS records

Open the domain’s **DNS Records** tab. Prontuno shows the exact type, hostname, value, and TTL for every record. Copy those values rather than using the examples below.

- Record | Purpose | Important note
- Return-path CNAME | Aligns bounce handling with your sending domain. | Publish the hostname and target exactly as displayed.
- DKIM CNAME 1 | Lets Prontuno sign your messages cryptographically. | Do not change the selector or target.
- DKIM CNAME 2 | Provides a second signing selector for safe key rotation. | Both DKIM records must verify.
- DMARC TXT | Defines how receiving servers handle authentication failures. | If a DMARC record already exists, do not create a second one.

### DNS providers may shorten hostnames

Some providers expect only the host portion and automatically append your domain. Others expect the full hostname. Check the provider’s preview before saving so your domain is not added twice.

## Check verification

Prontuno rechecks unverified records automatically every few minutes. Refresh the domain page to see the latest result. Most changes propagate quickly, but worldwide DNS caches can take up to 48 hours to update.

The domain is ready when the required return-path and both DKIM records show as verified. Once verified, you can create a sending API key or SMTP credential for the domain.

## About DMARC

Only one DMARC TXT record should exist at `_dmarc.your-domain`. If your domain already has one, leave it in place. If it does not, publish the value recommended by Prontuno.

When tightening an existing DMARC policy, review reports first and confirm that every legitimate sender for the domain is authenticated.

## Troubleshoot DNS verification

- **Still pending:** wait for propagation, then confirm the record exists on the authoritative nameservers.
- **Hostname repeated:** remove the duplicate domain suffix added by your DNS provider.
- **Wrong record type:** make sure CNAME records were not created as TXT records.
- **Proxy enabled:** if your DNS provider can proxy CNAME traffic, set email authentication records to DNS-only.
- **Conflicting record:** a CNAME hostname cannot normally have another record at the same name.
- **DMARC duplicate:** merge the intended policy into the existing DMARC record instead of publishing another.

You can also use **Send Setup Instructions** on the domain page to email the exact DNS values to an authorized administrator.

## Next steps

After verification, continue with [Send email with SMTP](https://prontuno.com/docs/sending/send-email-with-smtp/) or [Create and manage API keys](https://prontuno.com/docs/sending/api-keys/).